On 05-06-18, 16:31, Shreyas NC wrote:
From: Sanyog Kale sanyog.r.kale@intel.com
Add example and documentation to describe Multi Link streams
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Sanyog Kale sanyog.r.kale@intel.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Shreyas NC shreyas.nc@intel.com
Documentation/driver-api/soundwire/stream.rst | 30 ++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-)
diff --git a/Documentation/driver-api/soundwire/stream.rst b/Documentation/driver-api/soundwire/stream.rst index 29121aa..af9529b 100644 --- a/Documentation/driver-api/soundwire/stream.rst +++ b/Documentation/driver-api/soundwire/stream.rst @@ -76,7 +76,35 @@ Slaves are using single port. :: +---------------+
-Example 4: Stereo Stream with L and R channel is rendered by two different +Example 4: Stereo Stream with L and R channel is rendered by 2 Masters, each
We already have an example 4, shouldn't this be 5th one, can you check? I would prefer adding new example at the end and not in middle..
+rendering one channel, and is received by two different Slaves, each +receiving one channel. Both Masters and both Slaves are using single port. ::
- +---------------+ Clock Signal +---------------+
- | Master +----------------------------------+ Slave |
- | Interface | | Interface |
- | 1 | | 1 |
- | | Data Signal | |
- | L +----------------------------------+ L |
- | (Data) | Data Direction | (Data) |
- +---------------+ +-----------------------> +---------------+
- +---------------+ Clock Signal +---------------+
- | Master +----------------------------------+ Slave |
- | Interface | | Interface |
- | 2 | | 2 |
- | | Data Signal | |
- | R +----------------------------------+ R |
- | (Data) | Data Direction | (Data) |
- +---------------+ +-----------------------> +---------------+
+Note: In multi-link cases like above, to lock, one would acquire a global +lock and then go on locking bus instances. But, in this case the caller +framework(ASoC DPCM) guarantees that stream operations on a card are +always serialized. So, there is no race condition and hence no need for +global lock.
+Example 5: Stereo Stream with L and R channel is rendered by two different Ports of the Master and is received by only single Port of the Slave interface. ::
-- 2.7.4